Dopant-Free Two-Dimensional Hole Transport Small Molecules Enable Efficient Perovskite Solar Cells

Ji, Xiaofei1,2,3,4; Zhou, Tong1,2,3; Fu, Qiang1,2,3; Wang, Wenxuan1,2,3; Wu, Ziang1,2,3,5; Zhang, Mingtao1,2,3; Guo, Xugang4; Liu, Dongxue6; Woo, Han Young5; Liu, Yongsheng1,2,3,7

2023

10.1002/aenm.202203756

Advanced Energy Materials   Impact Factor & Quartile

1614-6832

1614-6840

Developing dopant-free hole transport materials (HTMs) to replace Spiro-OMeTAD is a challenging but urgent issue for commercialization of state-of-the-art n-i-p structured perovskite solar cells (PSCs). Here, this work proposes an effective two-dimensional conjugate engineering strategy to tune molecular stacking orientation and improve the hole mobility of dopant-free small molecule HTMs. For the first time, triphenylamine (TPA) groups are incorporated as side chains of benzo [1,2-b:4,5-b ']dithiophene (BDT) unit to extend the longitudinal conjugate, achieving two donor-acceptor-acceptor type 2D small molecules, namely XF2 and XF3, which show a dominant face-on orientation and better hole transport mobility than the linear small molecule XF1. The incorporation of alkoxy Lewis base groups makes XF3 a more effective defect passivator for perovskite surfaces. As a result, the PSCs using pristine XF3 HTM show a dramatically improved efficiency of 20.59% along with improved long-term stability compared to that of XF1 HTM (power conversion efficiency (PCE) = 18.84%). A champion efficiency of 21.44% is achieved through device engineering for dopant-free XF3-based PSCs. The results show that the building block with longitudinal conjugate extension in small molecules plays an essential role in the face-on orientation morphology and elucidates a key design rule for the dopant-free small molecule HTMs for high-performance PSCs.

defect passivation dopant-free hole transport materials perovskite solar cells two-dimensional conjugated molecules

SCI

English

Corresponding

National Natural Science Foundation of China["52273182","21875122"] ; National Key Research and Development Program of China[2019YFA0705900] ; Shenzhen Science and Technology Innovation Commission[JCYJ20220818100617037] ; Natural Science Foundation of Hebei Province[B2022408005]

Chemistry ; Energy & Fuels ; Materials Science ; Physics

Chemistry, Physical ; Energy & Fuels ; Materials Science, Multidisciplinary ; Physics, Applied ; Physics, Condensed Matter

WOS:000920145500001

WILEY-V C H VERLAG GMBH

Web of Science

1.Nankai Univ, Ctr Nanoscale Sci & Technol, Tianjin 300071, Peoples R China
2.Nankai Univ, Inst Polymer Chem, Coll Chem, Key Lab Funct Polymer Mat, Tianjin 300071, Peoples R China
3.Nankai Univ, Renewable Energy Convers & Storage Ctr RECAST, Tianjin 300071, Peoples R China
4.Southern Univ Sci & Technol SUSTech, Dept Mat Sci & Engn, Shenzhen 518055, Guangdong, Peoples R China
5.Korea Univ, Dept Chem, Seoul 02841, South Korea
6.China Three Gorges Corp, Renewable Energy & New Power Syst Engn Res Ctr, Beijing 100038, Peoples R China
7.Haihe Lab Sustainable Chem Transformat, Tianjin 300192, Peoples R China

Ji, Xiaofei,Zhou, Tong,Fu, Qiang,et al. Dopant-Free Two-Dimensional Hole Transport Small Molecules Enable Efficient Perovskite Solar Cells[J]. Advanced Energy Materials,2023.

Ji, Xiaofei.,Zhou, Tong.,Fu, Qiang.,Wang, Wenxuan.,Wu, Ziang.,...&Liu, Yongsheng.(2023).Dopant-Free Two-Dimensional Hole Transport Small Molecules Enable Efficient Perovskite Solar Cells.Advanced Energy Materials.

Ji, Xiaofei,et al."Dopant-Free Two-Dimensional Hole Transport Small Molecules Enable Efficient Perovskite Solar Cells".Advanced Energy Materials (2023).